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    <title>Title</title>
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        html{
            font-size: 16px;
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        *{
            margin: 0;
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        div{
            height: 100px;
            width: 100px;
            background-color: aqua;
            border: 1px solid black;
            margin-top:20px ;
            padding-top:20px;
            padding-left: 20px;

        }
        span{
            font-size: 0.625rem;
        }
    </style>
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<body>
<!--  <script>-->
<!--    var num1 = '10';-->
<!--    var num2 = '10.5';-->
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  <div></div>
  <span>发生巨大的开发和开始打飞机</span>
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